Abstract

In medical diagnosis, as in many cognitive domains, asking the
right questions is crucial. Medical tests differ not only in the type of
information they provide, but in their financial costs and physical risks to a
patient. We develop a model that combines informational and cost constraints,
describing specific medical scenarios of a patient with realistic symptoms. We
then define a finite number of existing medical tests that are available in this
situation. The tests differ in their sensitivity and specificity concerning
different possible underlying diseases as well as in their financial costs and
the physical risks they pose to a patient. Combining these, we compare the
utilities of the different tests if performed alone as well as if performed in
combination. We show how purely informational considerations are not adequate for
the analysis of such a scenario; test costs and patient outcomes must also be
taken into account.